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Division Spotlight
Thermal Hydraulics
The division provides a forum for focused technical dialogue on thermal hydraulic technology in the nuclear industry. Specifically, this will include heat transfer and fluid mechanics involved in the utilization of nuclear energy. It is intended to attract the highest quality of theoretical and experimental work to ANS, including research on basic phenomena and application to nuclear system design.
Meeting Spotlight
2024 ANS Annual Conference
June 16–19, 2024
Las Vegas, NV|Mandalay Bay Resort and Casino
Standards Program
The Standards Committee is responsible for the development and maintenance of voluntary consensus standards that address the design, analysis, and operation of components, systems, and facilities related to the application of nuclear science and technology. Find out What’s New, check out the Standards Store, or Get Involved today!
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Commercial nuclear innovation "new space" age
In early 2006, a start-up company launched a small rocket from a tiny island in the Pacific. It exploded, showering the island with debris. A year later, a second launch attempt sent a rocket to space but failed to make orbit, burning up in the atmosphere. Another year brought a third attempt—and a third failure. The following month, in September 2008, the company used the last of its funds to launch a fourth rocket. It reached orbit, making history as the first privately funded liquid-fueled rocket to do so.
M. K. Sheaffer, M. J. Driscoll, I. Kaplan
Nuclear Science and Engineering | Volume 48 | Number 4 | August 1972 | Pages 459-466
Technical Paper | doi.org/10.13182/NSE72-A22513
Articles are hosted by Taylor and Francis Online.
A one-group method for the calculation of neutron balances in fast reactor cores is developed and evaluated. The key feature of the method is the definition of two spectrum characterization parameters in terms of spectrum-averaged one-group cross sections for the homogenized core composition: where ξel is the mean logarithmic energy decrement for elastic moderation and ∑f, ∑TR, and are fission, transport, and removal cross sections, respectively. All required cross sections can then be correlated in the form = σ1 Sg (where and g are constants; one pair of values correlated for each cross section) except for threshold fission for which = σ1Rg. A rapidly converging iterative procedure is presented through which S and R can be determined for any core composition. Microscopic cross-section data are correlated in the above form using the 26-group ABBN multigroup set as parent data. The one-group method is tested for 45 different fast reactor core compositions by comparing the results of the one-group calculations with those of 26-group calculations. The results are found to agree within an average error of ±1.77% in the material buckling or to ±0.69% in effective multiplication factor. One-group relationships are also developed for the calculation ofprompt-neutron lifetime, Doppler reactivity, and other parameters of interest.